Serious childhood illnesses: 0-3 years

Recognising serious illnesses in babies and young children can be hard, because the early signs of many childhood illnesses look similar. This guide helps you recognise signs of serious illnesses and explains what to do.

Drowsiness and unresponsiveness
It’s normal for your child to be sleepy sometimes – for example, after a feed. But if your child seems sleepier than usual, this can be a sign of serious childhood illnesses.

If you can’t wake up your child even when you try really hard many times, get help immediately.

Unresponsiveness can be a sign of several serious childhood illnesses and conditions, including low blood sugar (hypoglycaemia) or a life-threatening brain infection (meningitis).

High-pitched, weak or continuous crying
All babies and young children cry. But if your child is crying in an unusual way, the crying doesn’t stop, and you have trouble settling your child, you should be concerned.

Non-blanching rash (positive glass test)
Skin spots or blotches that don’t fade when you press directly on your child’s skin can be an early sign of life-threatening meningococcal infection.

You can do the ‘glass test’ by pressing the side of a clear glass firmly against the rash on your child’s skin. If the spot or rash doesn’t disappear when you do this, it might be a medical emergency. Call 000 and ask for an ambulance.

When to go to the hospital emergency department for childhood illnesses

If you notice any of the following signs and symptoms take your child straight to the nearest emergency department:

a temperature above 38°C in babies less than three months old

poor urine output

poor feeding

frequent vomiting.

There is more information about these signs and symptoms below.

High temperature above 38°C
A high temperature is the body’s normal way of fighting infections. Most children with a high temperature don’t have a serious illness. But in some cases, a high temperature can be a sign of serious infection.

If your baby is under three months and develops a high temperature, a doctor needs to see her immediately. This is because it’s harder to tell whether children in this age group have serious underlying illnesses.

But if your child is over three months and doesn’t show other signs of serious illness, you could also take your child to the GP if you can get an appointment on the same day.

Feeling your child’s skin temperature (for example, by putting your hand to his forehead) isn’t always a reliable way of diagnosing a fever. The best way to check your child’s temperature is with a thermometer.

There are several different methods for taking a child’s temperature using a thermometer:

orally – putting a digital thermometer in your child’s mouth under the tongue

rectally – putting the thermometer a little way into your baby’s rectum

axillary – putting the thermometer under your child’s armpit

aurally – putting a digital ear thermometer into your child’s ear, which can be a little inaccurate

Poor urine output
An early sign of many serious illnesses is fewer wet nappies than usual – that is, fewer than half the number of wet nappies your child usually has each day. It could mean your child is dehydrated.

Poor feeding
If your child isn’t feeding well or has no interest in feeding, this could be an early sign of childhood illness.

Frequent vomiting
Vomiting is a normal way for the body to get rid of something it doesn’t want. But vomiting that doesn’t stop can cause dehydration and dangerous imbalances in the body’s chemical system.

If your child can’t eat or drink anything and is still vomiting after 24 hours (or 12 hours for children under two years), go to the emergency department.

VideoSigns of serious illness

This short video features paediatrician Dr Con James discussing the signs of serious illness in babies and young children. He says you should always seek medical advice from a GP or hospital when you think there's a problem or when children are very unwell.

If you need urgent medical advice or information, you can phone Healthdirect on 1800 022 222. This helpline is available 24 hours a day.

Allen, C.H. (2014). Fever without a source in children 3 to 36 months of age. UpToDate. Retrieved 24 March 2017 from http://www.uptodate.com/contents/fever-without-a-source-in-children-3-to-36-months-of-age.

National Institute for Health and Care Excellence (2013). Feverish illness in children: Assessment and initial management in children younger than 5 years. London: National Institute for Health and Care Excellence. Retrieved 24 March 2017 from https://www.nice.org.uk/guidance/cg160.